FCSF-ePTFE membrane takes polytetrafluoro ethylene (PTFE) as raw material, which is made of special process. The surface of membrane is covered with fibrous micropores, which have up to 90 billion micropores per square inch, with excellent waterproof, breathable, water vapor permeability, keeping warm effect.
The hydrostatic pressure for FCSF-ePTFE membrane could reach up to about 18000mm of the water column, which can withstand heavy rain. The U.S. military standards are only 7000mm water column.
The micropore diameter of the FCSF-ePTFE membrane is about 0.2μm, the diameter of light rain is 400μm, the diameter of heavy rain is 3000μm, the diameter of rainstorm is 6000 μm above. So whether the rain is light or heavy, fcsf-ePTFE membrane can effectively block them.
The water vapor permeability for FCSF-ePTFE membrane could reach 32603g/m2.24hr, and the general waterproof breathable fabric is only 2000-3000g/m2.24hr.
Due to the diameter of water vapor molecule is 0.0004μm, and the micropore diameter of FCSF-ePTFE membrane are a few hundred times greater than water vapor molecules, and at the same time with the drive of temperature difference and the vapor concentration difference inside and outside the membrane, so sweat vapor easily excreted through the micropores, and will not accumulate and condensate between skin and fabric, and make human body to keep dry and comfortable.
The index which mostly reflect the fabric water vapor permeability performance is water vapor resistance. The FCSF-ePTFE membrane of the water vapor diffusion resistance is less than 4, and its performance is much better than domestic and international similar products.